000
AGXX40 KNHC 070638
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
240 AM EDT FRI AUG 07 2009

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA
AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.

SW ATLC W OF 55W...
A RIDGE EXTENDING FROM 31N67W TO CENTRAL FLORIDA CONTINUES TO
BE THE DOMINANT FEATURE OF THE AREA MAINTAINING GENERALLY LIGHT
CONDITIONS AS SEEN IN BUOY...SHIP AND SCATTEROMETER DATA FROM 
TONIGHT. THE RIDGE IS EXPECTED TO ERODE AS THE COLD FRONT 
CURRENTLY OVER THE EASTERN CAROLINAS SWINGS 
SOUTHEASTWARD...REACHING 30N BY SAT NIGHT. A SURFACE TROUGH NE 
OF THE BAHAMAS WILL MOVE NORTHWARD INTO THE LEADING EDGE OF 
TROUGH SUPPORTING THE COLD FRONT. AT THE SAME TIME...A TROPICAL 
WAVE WILL PASS W THROUGH THE CENTRAL CARIBBEAN. SE WINDS OF 
15 TO 20 KT OVER SOME OF THE WATERS S AND SW OF THE BAHAMAS WILL 
CONTINUE THROUGH TUE WITH SEAS 4-6 FT E OF THE BAHAMAS...AND 3 
TO 5 FT W AND SW OF THE BAHAMAS. MODEL GUIDANCE ALSO SUGGESTS 
BACKING NE WINDS OVER THE SE WATERS AS A TROPICAL LOW PRES 
APPROACHES FROM THE CENTRAL TROPICAL ATLC. OBVIOUSLY SOME 
UNCERTAINTY IS EXPECTED IN DAYS 4 AND 5 OF THE FORECAST.

TROPICAL ATLC AND CARIBBEAN SEA...
A TROPICAL WAVE ALONG 84W IS MOVING W ABOUT 15 KT. THE WAVE WILL 
MOVE THROUGH THE GULF OF HONDURAS FRI. A SECOND TROPICAL WAVE 
ALONG 67W IS ALSO MOVING W ABOUT 15 KT. DESPITE DEEP LAYER 
MOISTURE ASSOCIATED WITH THE WAVE AND THE SOUTHEAST SIDE OF THE 
UPPER LOW NEAR 25N65W...PRESENTLY THE WAVE DOES NOT APPEAR TO BE 
VERY CONVECTIVE RIGHT ALONG ITS AXIS. THE WAVE WILL MOVE THROUGH 
THE CENTRAL PORTION OF THE CARIBBEAN FRI...AND ACROSS THE 
WESTERN PORTION OVER THE WEEKEND. 

ANOTHER WAVE IN THE CENTRAL ATLC PRESENTS THE MOST UNCERTAINTY 
AS IT HAS A HISTORY OF INDUCING SMALL CYCLONIC CIRCULATION WHICH 
HAS BEEN RE-INTRODUCED ON THE 06Z SURFACE ANALYSIS. LATEST 
GLOBAL MODEL GUIDANCE AGAIN HINTS AT SOME FORM OF A LOW TRACKING 
WNW WITH THE TROUGH OVER THE NEXT FEW DAYS. TRADES WILL CONTINUE 
IN THE 20-25 KT RANGE OVER MUCH OF THE CENTRAL CARIBBEAN...WITH 
THE POSSIBILITY OF 25-30 KT ALONG OR NEAR THE COAST OF COLOMBIA 
FRI NIGHT INTO SUN MORNING DUE TO TIGHT PRES GRADIENT CREATED BY 
ATLC HIGH PRES CENTERED OVER THE WESTERN ATLC AND LOW PRES OVER 
COLOMBIA AND PANAMA. LATEST WAVEWATCH BUILDS SEAS NEAR THE COAST 
OF COLOMBIA TO 13 FT DURING THE WEEKEND.

GULF OF MEXICO...
A WEAK PRES GRADIENT WILL PREVAIL ACROSS THE AREA THROUGH TUE AS 
THE WESTERN EXTENSION OF AN ATLC RIDGE CONTINUES OVER THE FAR 
NORTHERN WATERS. BOTH BUOY OBSERVATIONS AND A QUIKSCAT PASS FROM 
0056 UTC SHOWED LIGHT WINDS WITH THE BUOYS REPORTING SEAS OF 1-2 
FT. THIS IS IN GOOD AGREEMENT WITH THE 12 UTC NOAA WAVEWATCH 
MODEL GUIDANCE. BOTH THE DETERMINISTIC GFS...AND CORRESPONDING 
ENSEMBLE SOLN AGREE THAT THE RIDGE WILL HOLD THROUGH TUE WITH 
LITTLER OVERALL CHANGE IN PRESENT CONDITIONS. THE NORTHERN 
PORTION OF A TROPICAL WAVE IS EXPECTED TO MOVE W ACROSS THE SW 
GULF WATERS FRI/SAT.
 

WARNINGS

ATLC...
.NONE. 

CARIBBEAN...
.NONE. 

GULF OF MEXICO...
.NONE.

$$
FORECASTER SCHAUER CLARK/AGUIRRE